Some users have recently had their accounts hijacked. It seems that the now defunct EVGA forums might have compromised your password there and seems many are using the same PW here. We would suggest you UPDATE YOUR PASSWORD and TURN ON 2FA for your account here to further secure it. None of the compromised accounts had 2FA turned on.
Once you have enabled 2FA, your account will be updated soon to show a badge, letting other members know that you use 2FA to protect your account. This should be beneficial for everyone that uses FSFT.
The z-2300's would be a good bet if your looking for something less expensive with a heavy sub in the 2.1 PC speakers department. I've had a couple sets of them and they sound pretty good. I just upgraded to the z-5500's though and HOLY CRAP!!
If you've got the right connectors you can hook a car subwoofer up to a home sound system, but be forewarned, a car subwoofer won't sound as great as it does in a car as it will in your room, the sound environment is MUCH different.